Tripling Plywood for a 150 lb Plasma TV "corner" mount

I want to make a strong "triangle shaped mount" above a fireplace that is in a corner. Since I am doing this to create a "wall" for a Plasma TV in this corner (plasma tvs' cannot be mounted into "corners"), I want this project to be as strong as possible, because the plasma tv is 150 lbs. I therefore plan on creating this triangular piece that will be about 25" high and 35" wide. with a base triangle and a top triangle, all of which made of plywood (combined 3 pieces of the thickest plywood Home Depot sells).

Do you have any ideas on how to do this? And how do you think I should connect this to the wall? Screws, bolts?

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Tripling Plywood for a 150 lb Plasma TV "corner" mount

I would cut out the drywall where this is to go and nail 2X4 or 2X6 framing for the plywood triangles directly to the wall (and possibly ceiling) studs.
You need framing for something that heavy, not just a plywood "box".
Use 3/4" plywood on the framing.
Good luck!
Mike

Tripling Plywood for a 150 lb Plasma TV "corner" mount

I personally would go with the plywood box construction here, and mount it right over the existing drywall. Cut two plywood "sides 25" high by whatever length they need to be so that you end up with the "face" width you need. Set your saw to cut the front edges at a 45 degree angle. These pieces will cross at least two and possibly three studs including the corner of the wall; the 25" height allowing you to get 4 or five screws into each stud. Next. fit the top and bottom triangles and screw them to the side pieces. So that there is plenty wood at the front corners, rip a 45 degree bevel on a couple of pieces of 2 by and fasten them vertically so they line up with the bevels on the plywood sides. If you want to add a couple of "studs" across the face for piece of mind go ahead. All of your wiring should be pulled to the front of the open faced triangle now, for easy access. Now cut a piece of plywood to close the face of the box, fastening with long screws that will go through both the beveled vertical corner blocks and into the plywood sides, then screw the plywood to any "studs" you installed, and to the top and bottom plywood pieces. If you located the "studs" so they align with the holes in your mounting bracket, you are ready to cover the box with drywall, if you are not to sure of this alignment, add a second layer of plywood to the face, using long screws at the vertical corners again and spotting 1 1/2" screws around the face to secure the two layers together, giving you a full 1 1/2" face to fasten the mounting bracket into.
This box will support more weight than you could possibly ever hang on it, and working with the pieces of plywood is a lot less aggravating than framing it with individual pieces of lumber, although there is nothing wrong with doing it like that.

Tripling Plywood for a 150 lb Plasma TV "corner" mount

Problem with 45 degree angles, is that Triangles do not have 45 degree angles. Personally, if I was mounting on a corner, I would go with the mount that Jeekins shows that is available for this kind of situation.

Tripling Plywood for a 150 lb Plasma TV "corner" mount

Quote:

Originally Posted by gregzoll

Problem with 45 degree angles, is that Triangles do not have 45 degree angles. Personally, if I was mounting on a corner, I would go with the mount that Jeekins shows that is available for this kind of situation.

Too bad to here that. Obviously another person who thought they would never use any of that stuff, so you slept through geomety
If you come out the same distance on both walls from the inside corner, and connect the front edge with a diagonal plane, what angle do you plan on getting?

Hints: equilateral triangle
Theorem: The sum of all the angles of any triangle will always be 180
degrees.
Think common speed square.

Tripling Plywood for a 150 lb Plasma TV "corner" mount

I meant Pyramid. My fault. From what the other person will end up doing, is creating in theory a Pyramid, not just three pieces in a Tri-angle. It ends up being more of a PITA, then just buying something that is already created for the job.

Tripling Plywood for a 150 lb Plasma TV "corner" mount

Can't argue the point that it is certainly more work than sticking it on a metal bracket, but IMO these screens just stuck to the wall in ridiculous places are ugly enough when they are on a flat surface, much less sticking out across a corner on some bracket that looks more suited to a warehouse security monitor than a tv in your house.

Tripling Plywood for a 150 lb Plasma TV "corner" mount

Like I said, 2-3 sheets of good ply will run 30-40 a sheet, framing, labor and hardware. You could just buy the mount. Not to mention the risk of damaging the television trying to fabricate the mount.

I have also seen a variation that attaches to the ceiling.

I'm not suggesting that he still will not have to buy a wall mounting bracket, no way I would try to jury rig something to the back of a new tv, just that IMO it would be much more asthetically pleasing to have the unit mounted onto a flat surface that looked like part of the room, as opposed to a screen hanging across the corner of a room on a visible, institutional looking bracket, which is still going to require some surgery on the wall to install wood blocking to bolt this thing to.
I happen to always prefer the asthetically pleasing solutions to the get R done solutions. Granted they are always more costly and time consumming.